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#include <stdio.h>
#include <stdlib.h>
#include <time.h>
typedef struct {
int x, y;
} vec2;
typedef struct {
vec2 min;
vec2 max;
} range;
#define IN_RANGE(pos, range) \
(pos.x >= range.min.x && pos.x <= range.max.x && pos.y >= range.min.y && \
pos.y <= range.max.y)
#define ADD(a, b) (a = (vec2){ a.x + b.x, a.y + b.y })
#define DRAG(x) ((x) < 0 ? (x)++ : (x) > 0 ? (x)-- : (x))
static int hits(vec2 velocity, range target)
{
vec2 pos = { 0 };
while (ADD(pos, velocity), DRAG(velocity.x), velocity.y--, pos.y >= target.min.y)
if (IN_RANGE(pos, target))
return 1; // Hit!
return 0;
}
static void solve(FILE *fp)
{
int first = 0, second = 0;
range target;
fscanf(fp, "target area: x=%d..%d, y=%d..%d\n", &target.min.x, &target.max.x, &target.min.y,
&target.max.y);
vec2 velocity;
for (velocity.y = target.min.y; velocity.y <= -target.min.y; velocity.y++) {
for (velocity.x = 0; velocity.x <= target.max.x; velocity.x++) {
if (hits(velocity, target)) {
second++;
int height = velocity.y * (velocity.y + 1) / 2;
if (height > first)
first = height;
}
}
}
printf("%d\n%d\n", first, second);
}
int main(int argc, char *argv[])
{
(void)argc;
(void)argv;
FILE *fp = fopen("input", "r");
if (!fp)
exit(EXIT_FAILURE);
clock_t tic = clock();
solve(fp);
clock_t toc = clock();
printf("TIME: %f seconds\n", (double)(toc - tic) / CLOCKS_PER_SEC);
fclose(fp);
return 0;
}
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